extern int write_ref_sha1(struct ref_lock *lock, const unsigned char *sha1, const char *msg);
/** Reads log for the value of ref during at_time. **/
-extern int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1);
+extern int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
+
+/* iterate over reflog entries */
+typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
+int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data);
/** Returns 0 if target has the right format for a ref. **/
extern int check_ref_format(const char *target);